HomogeneousMatrix¶
- class HomogeneousMatrix(*args, **kwargs)¶
Bases:
ArrayDouble2D
Implementation of an homogeneous matrix and operations on such kind of matrices.
The class provides a data structure for the homogeneous matrices as well as a set of operations on these matrices.
The vpHomogeneousMatrix class is derived from vpArray2D<double> .
An homogeneous matrix is 4x4 matrix defines as
\[\begin{split}^a{\bf M}_b = \left(\begin{array}{cc} ^a{\bf R}_b & ^a{\bf t}_b \\{\bf 0}_{1\times 3} & 1 \end{array} \right) \end{split}\]that defines the position of frame b in frame a
\(^a{\bf R}_b\) is a rotation matrix and \(^a{\bf t}_b\) is a translation vector.
There are different ways to initialize an homogeneous matrix. You can set each element of the matrix like:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix M; M[0][0] = 0; M[0][1] = 0; M[0][2] = -1; M[0][3] = 0.1; M[1][0] = 0; M[1][1] = -1; M[1][2] = 0; M[1][3] = 0.2; M[2][0] = -1; M[2][1] = 0; M[2][2] = 0; M[2][3] = 0.3; std::cout << "M:" << std::endl; for (unsigned int i = 0; i < M.getRows(); ++i) { for (unsigned int j = 0; j < M.getCols(); ++j) { std::cout << M[i][j] << " "; } std::cout << std::endl; } }
It produces the following printings:
M: 0 0 -1 0.1 0 -1 0 0.2 -1 0 0 0.3 0 0 0 1
You can also use vpRotationMatrix::operator<< and vpTranslationVector::operator<< like:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpTranslationVector t; vpRotationMatrix R; R << 0, 0, -1, 0, -1, 0, -1, 0, 0; t << 0.1, 0.2, 0.3; vpHomogeneousMatrix M(t, R); std::cout << "M:\n" << M << std::endl; }
If ViSP is build with c++11 enabled, you can do the same using:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { { vpHomogeneousMatrix M( vpTranslationVector(0.1, 0.2, 0.3), vpRotationMatrix( {0, 0, -1, 0, -1, 0, -1, 0, 0} ) ); std::cout << "M:\n" << M << std::endl; } { vpHomogeneousMatrix M { 0, 0, -1, 0.1, 0, -1, 0, 0.2, -1, 0, 0, 0.3 }; std::cout << "M:\n" << M << std::endl; } }
JSON serialization
Since ViSP 3.6.0, if ViSP is build with soft_tool_json 3rd-party we introduce JSON serialization capabilities for vpHomogeneousMatrix . The following sample code shows how to save a homogeneous matrix in a file named homo-mat.json and reload the values from this JSON file.
#include <visp3/core/vpHomogeneousMatrix.h> int main() { #if defined(VISP_HAVE_NLOHMANN_JSON) std::string filename = "homo-mat.json"; { vpHomogeneousMatrix M(vpTranslationVector(0.1, 0.2, 0.3), vpRotationMatrix({ 0, 0, -1, 0, -1, 0, -1, 0, 0 })); std::ofstream file(filename); const nlohmann::json j = M; file << j; file.close(); } { std::ifstream file(filename); const nlohmann::json j = nlohmann::json::parse(file); vpHomogeneousMatrix M; M = j; file.close(); std::cout << "Read homogeneous matrix from " << filename << ":\n" << M << std::endl; } #endif }
If you build and execute the sample code, it will produce the following output:
Read homogeneous matrix from homo-mat.json: 0 0 -1 0.1 0 -1 0 0.2 -1 0 0 0.3 0 0 0 1
The content of the homo-mat.json file is the following:
$ cat homo-mat.json {"cols":4,"data":[0.0,0.0,-1.0,0.1,0.0,-1.0,0.0,0.2,-1.0,0.0,0.0,0.3,0.0,0.0,0.0,1.0],"rows":4,"type":"vpHomogeneousMatrix"}
Overloaded function.
__init__(self: visp._visp.core.HomogeneousMatrix) -> None
Default constructor that initialize an homogeneous matrix as identity.
__init__(self: visp._visp.core.HomogeneousMatrix, M: visp._visp.core.HomogeneousMatrix) -> None
Copy constructor that initialize an homogeneous matrix from another homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, R: visp._visp.core.RotationMatrix) -> None
Construct an homogeneous matrix from a translation vector and a rotation matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, tu: visp._visp.core.ThetaUVector) -> None
Construct an homogeneous matrix from a translation vector and \(\theta {\bf u}\) rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, q: visp._visp.core.QuaternionVector) -> None
Construct an homogeneous matrix from a translation vector and quaternion rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, p: visp._visp.core.PoseVector) -> None
Construct an homogeneous matrix from a pose vector.
__init__(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Construct an homogeneous matrix from a vector of float.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<float> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3000000119 1 0 0 0.400000006 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Construct an homogeneous matrix from a vector of double.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<double> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, tx: float, ty: float, tz: float, tux: float, tuy: float, tuz: float) -> None
Construct an homogeneous matrix from a translation vector \({\bf t}=(t_x, t_y, t_z)^T\) and a \(\theta {\bf u}=(\theta u_x, \theta u_y, \theta u_z)^T\) rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, list: std::initializer_list<double>) -> None
Construct an homogeneous matrix from a list of 12 or 16 double values.
- Parameters:
- list
List of double. The following code shows how to use this constructor to initialize an homogeneous matrix:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix M { 0, 0, 1, 0.1, 0, 1, 0, 0.2, 1, 0, 0, 0.3 }; std::cout << "M:\n" << M << std::endl; vpHomogeneousMatrix N { 0, 0, 1, 0.1, 0, 1, 0, 0.2, 1, 0, 0, 0.3, 0, 0, 0, 1 }; std::cout << "N:\n" << N << std::endl; }
It produces the following output:
M: 0 0 1 0.1 0 1 0 0.2 1 0 0 0.3 0 0 0 1 N: 0 0 1 0.1 0 1 0 0.2 1 0 0 0.3 0 0 0 1
__init__(self: visp._visp.core.HomogeneousMatrix, np_array: numpy.ndarray[numpy.float64]) -> None
Construct a homogeneous matrix by copying a 2D numpy array. This numpy array should be of dimensions \(4 \times 4\) and be a valid homogeneous matrix. If it is not a homogeneous matrix, an exception will be raised.
- Parameters:
- np_array
The numpy 1D array to copy.
Methods
Overloaded function.
Overloaded function.
- param p:
First point cloud.
Converts an homogeneous matrix to a vector of 12 doubles.
Overloaded function.
Set transformation to identity.
The following example shows how to use this function:
Return the rotation matrix from the homogeneous transformation matrix.
Return the \(\theta {\bf u}\) vector that corresponds to the rotation part of the homogeneous transformation.
Return the translation vector from the homogeneous transformation matrix.
Overloaded function.
Overloaded function.
Test if the 3x3 rotational part of the homogeneous matrix is a valid rotation matrix and the last row is equal to [0, 0, 0, 1].
- return:
true when no NaN found, false otherwise.
Overloaded function.
Compute the Euclidean mean of the homogeneous matrices.
Numpy view of the underlying array data.
Perform orthogonalization of the rotation part of the homogeneous transformation.
Print the matrix as a pose vector \(({\bf t}^T \theta {\bf u}^T)\) .
Overloaded function.
Overloaded function.
Inherited Methods
Return the number of columns of the 2D array.
Insert array B in array A at the given position.
Return the number of rows of the 2D array.
Return the number of elements of the 2D array.
Return the array min value.
Return the array max value.
- param m:
Second matrix;
Save an array in a YAML-formatted file.
Overloaded function.
Compute the transpose of the array.
Operators
__doc__
Overloaded function.
Operator that allow to multiply an homogeneous matrix by an other one.
Overloaded function.
__module__
Overloaded function.
Attributes
__annotations__
- __eq__(*args, **kwargs)¶
Overloaded function.
__eq__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Equal to comparison operator of a 2D array.
__eq__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Equal to comparison operator of a 2D array.
__eq__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Equal to comparison operator of a 2D array.
- __getitem__(*args, **kwargs)¶
Overloaded function.
__getitem__(self: visp._visp.core.HomogeneousMatrix, arg0: tuple[int, int]) -> float
__getitem__(self: visp._visp.core.HomogeneousMatrix, arg0: int) -> numpy.ndarray[numpy.float64]
__getitem__(self: visp._visp.core.HomogeneousMatrix, arg0: slice) -> numpy.ndarray[numpy.float64]
__getitem__(self: visp._visp.core.HomogeneousMatrix, arg0: tuple) -> numpy.ndarray[numpy.float64]
- __imul__(self, M: visp._visp.core.HomogeneousMatrix) visp._visp.core.HomogeneousMatrix ¶
Operator that allow to multiply an homogeneous matrix by an other one.
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix M1, M2; // Initialize M1 and M2... // Compute M1 = M1 * M2 M1 *= M2; }
- __init__(*args, **kwargs)¶
Overloaded function.
__init__(self: visp._visp.core.HomogeneousMatrix) -> None
Default constructor that initialize an homogeneous matrix as identity.
__init__(self: visp._visp.core.HomogeneousMatrix, M: visp._visp.core.HomogeneousMatrix) -> None
Copy constructor that initialize an homogeneous matrix from another homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, R: visp._visp.core.RotationMatrix) -> None
Construct an homogeneous matrix from a translation vector and a rotation matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, tu: visp._visp.core.ThetaUVector) -> None
Construct an homogeneous matrix from a translation vector and \(\theta {\bf u}\) rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, q: visp._visp.core.QuaternionVector) -> None
Construct an homogeneous matrix from a translation vector and quaternion rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, p: visp._visp.core.PoseVector) -> None
Construct an homogeneous matrix from a pose vector.
__init__(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Construct an homogeneous matrix from a vector of float.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<float> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3000000119 1 0 0 0.400000006 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Construct an homogeneous matrix from a vector of double.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<double> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
__init__(self: visp._visp.core.HomogeneousMatrix, tx: float, ty: float, tz: float, tux: float, tuy: float, tuz: float) -> None
Construct an homogeneous matrix from a translation vector \({\bf t}=(t_x, t_y, t_z)^T\) and a \(\theta {\bf u}=(\theta u_x, \theta u_y, \theta u_z)^T\) rotation vector.
__init__(self: visp._visp.core.HomogeneousMatrix, list: std::initializer_list<double>) -> None
Construct an homogeneous matrix from a list of 12 or 16 double values.
- Parameters:
- list
List of double. The following code shows how to use this constructor to initialize an homogeneous matrix:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix M { 0, 0, 1, 0.1, 0, 1, 0, 0.2, 1, 0, 0, 0.3 }; std::cout << "M:\n" << M << std::endl; vpHomogeneousMatrix N { 0, 0, 1, 0.1, 0, 1, 0, 0.2, 1, 0, 0, 0.3, 0, 0, 0, 1 }; std::cout << "N:\n" << N << std::endl; }
It produces the following output:
M: 0 0 1 0.1 0 1 0 0.2 1 0 0 0.3 0 0 0 1 N: 0 0 1 0.1 0 1 0 0.2 1 0 0 0.3 0 0 0 1
__init__(self: visp._visp.core.HomogeneousMatrix, np_array: numpy.ndarray[numpy.float64]) -> None
Construct a homogeneous matrix by copying a 2D numpy array. This numpy array should be of dimensions \(4 \times 4\) and be a valid homogeneous matrix. If it is not a homogeneous matrix, an exception will be raised.
- Parameters:
- np_array
The numpy 1D array to copy.
- __mul__(*args, **kwargs)¶
Overloaded function.
__mul__(self: visp._visp.core.HomogeneousMatrix, M: visp._visp.core.HomogeneousMatrix) -> visp._visp.core.HomogeneousMatrix
Operator that allow to multiply an homogeneous matrix by an other one.
#include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix aMb, bMc; // Initialize aMb and bMc... // Compute aMc * bMc vpHomogeneousMatrix aMc = aMb * bMc; }
__mul__(self: visp._visp.core.HomogeneousMatrix, v: visp._visp.core.ColVector) -> visp._visp.core.ColVector
Operator that allow to multiply an homogeneous matrix by a 4-dimension column vector.
__mul__(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector) -> visp._visp.core.TranslationVector
Since a translation vector could be seen as the origin point of a frame, this function computes the new coordinates of a translation vector after applying an homogeneous transformation.
- Parameters:
- t
Translation vector seen as the 3D coordinates of a point.
- Returns:
A translation vector that contains the new 3D coordinates after applying the homogeneous transformation.
__mul__(self: visp._visp.core.HomogeneousMatrix, R: visp._visp.core.RotationMatrix) -> visp._visp.core.HomogeneousMatrix
Operator that allows to multiply a rotation matrix by a rotation matrix.
The following snippet shows how to use this method:
vpHomogeneousMatrix c1_M_c2; vpRotationMatrix c2_R_c3; vpHomogeneousMatrix c1_M_c3 = c1_M_c2 * c2_R_c3;
- Parameters:
- R
Rotation matrix.
- Returns:
The product between the homogeneous matrix and the rotation matrix R .
__mul__(self: visp._visp.core.HomogeneousMatrix, bP: visp._visp.core.Point) -> visp._visp.core.Point
From the coordinates of the point in camera frame b and the transformation between camera frame a and camera frame b computes the coordinates of the point in camera frame a.
- Parameters:
- bP
3D coordinates of the point in camera frame bP.
- Returns:
A point with 3D coordinates in the camera frame a. The coordinates in the world or object frame are set to the same coordinates than the one in the camera frame.
- __ne__(*args, **kwargs)¶
Overloaded function.
__ne__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Not equal to comparison operator of a 2D array.
__ne__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Not equal to comparison operator of a 2D array.
__ne__(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D) -> bool
Not equal to comparison operator of a 2D array.
- buildFrom(*args, **kwargs)¶
Overloaded function.
buildFrom(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, R: visp._visp.core.RotationMatrix) -> None
Build an homogeneous matrix from a translation vector and a rotation matrix.
buildFrom(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, tu: visp._visp.core.ThetaUVector) -> None
Build an homogeneous matrix from a translation vector and a \(\theta {\bf u}\) rotation vector.
buildFrom(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector, q: visp._visp.core.QuaternionVector) -> None
Build an homogeneous matrix from a translation vector and a quaternion rotation vector.
buildFrom(self: visp._visp.core.HomogeneousMatrix, p: visp._visp.core.PoseVector) -> None
Build an homogeneous matrix from a pose vector.
buildFrom(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Build an homogeneous matrix from a vector of float.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<float> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M; M.buildFrom(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3000000119 1 0 0 0.400000006 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
buildFrom(self: visp._visp.core.HomogeneousMatrix, v: list[float]) -> None
Build an homogeneous matrix from a vector of double.The following example shows how to use this function:
#include <visp3/core/vpHomogeneousMatrix.h> int main() { std::vector<double> v(12, 0); v[1] = -1.; // ry=-90 v[4] = 1.; // rx=90 v[10] = -1.; // rz=-90 v[3] = 0.3; // tx v[7] = 0.4; // ty v[11] = 0.5; // tz std::cout << "v: "; for(unsigned int i=0; i<v.size(); ++i) std::cout << v[i] << " "; std::cout << std::endl; vpHomogeneousMatrix M; M.buildFrom(v); std::cout << "M:\n" << M << std::endl; }
It produces the following printings:
v: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 M: 0 -1 0 0.3 1 0 0 0.4 0 0 -1 0.5 0 0 0 1
- Parameters:
- v
Vector of 12 or 16 values corresponding to the values of the homogeneous matrix.
buildFrom(self: visp._visp.core.HomogeneousMatrix, tx: float, ty: float, tz: float, tux: float, tuy: float, tuz: float) -> None
Build an homogeneous matrix from a translation vector \({\bf t}=(t_x, t_y, t_z)^T\) and a \(\theta {\bf u}=(\theta u_x, \theta u_y, \theta u_z)^T\) rotation vector.
- static compute3d3dTransformation(p: list[visp._visp.core.Point], q: list[visp._visp.core.Point]) visp._visp.core.HomogeneousMatrix ¶
- Parameters:
- p: list[visp._visp.core.Point]¶
First point cloud.
- q: list[visp._visp.core.Point]¶
Second point cloud.
- Returns:
The homogeneous transformation \({^p}{\bf M}_q\) .
- static conv2(*args, **kwargs)¶
Overloaded function.
conv2(M: visp._visp.core.ArrayDouble2D, kernel: visp._visp.core.ArrayDouble2D, mode: str) -> visp._visp.core.ArrayDouble2D
Perform a 2D convolution similar to Matlab conv2 function: \(M \star kernel\) .
<unparsed image <doxmlparser.compound.docImageType object at 0x7ff6a36292a0>>
Note
This is a very basic implementation that does not use FFT.
- Parameters:
- M
First matrix.
- kernel
Second matrix.
- mode
Convolution mode: “full” (default), “same”, “valid”.
conv2(M: visp._visp.core.ArrayDouble2D, kernel: visp._visp.core.ArrayDouble2D, res: visp._visp.core.ArrayDouble2D, mode: str) -> None
Perform a 2D convolution similar to Matlab conv2 function: \(M \star kernel\) .
<unparsed image <doxmlparser.compound.docImageType object at 0x7ff6a362aec0>>
Note
This is a very basic implementation that does not use FFT.
- Parameters:
- M
First array.
- kernel
Second array.
- res
Result.
- mode
Convolution mode: “full” (default), “same”, “valid”.
- convert(self) list[float] ¶
Converts an homogeneous matrix to a vector of 12 doubles.
- Returns:
A tuple containing:
M: Converted matrix.
- extract(*args, **kwargs)¶
Overloaded function.
extract(self: visp._visp.core.HomogeneousMatrix, R: visp._visp.core.RotationMatrix) -> None
Extract the rotational matrix from the homogeneous matrix.
- Parameters:
- R
rotational component as a rotation matrix.
extract(self: visp._visp.core.HomogeneousMatrix, tu: visp._visp.core.ThetaUVector) -> None
Extract the rotation as a \(\theta \bf u\) vector.
extract(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector) -> None
Extract the translation vector from the homogeneous matrix.
extract(self: visp._visp.core.HomogeneousMatrix, q: visp._visp.core.QuaternionVector) -> None
Extract the rotation as a quaternion.
- getCol(self, j: int) visp._visp.core.ColVector ¶
The following example shows how to use this function:
#include <visp3/core/vpColVector.h> #include <visp3/core/vpHomogeneousMatrix.h> int main() { vpHomogeneousMatrix M; vpColVector t = M.getCol(3); std::cout << "Last column: \n" << t << std::endl; }
It produces the following output:
Last column: 0 0 1 0
- getRotationMatrix(self) visp._visp.core.RotationMatrix ¶
Return the rotation matrix from the homogeneous transformation matrix.
- getThetaUVector(self) visp._visp.core.ThetaUVector ¶
Return the \(\theta {\bf u}\) vector that corresponds to the rotation part of the homogeneous transformation.
- getTranslationVector(self) visp._visp.core.TranslationVector ¶
Return the translation vector from the homogeneous transformation matrix.
- hadamard(self, m: visp._visp.core.ArrayDouble2D) visp._visp.core.ArrayDouble2D ¶
- Parameters:
- m: visp._visp.core.ArrayDouble2D¶
Second matrix;
- Returns:
m1.hadamard(m2) The Hadamard product : \(m1 \circ m2 = (m1 \circ m2)_{i,j} = (m1)_{i,j} (m2)_{i,j}\)
- insert(*args, **kwargs)¶
Overloaded function.
insert(self: visp._visp.core.HomogeneousMatrix, R: visp._visp.core.RotationMatrix) -> None
Insert the rotational component of the homogeneous matrix.
insert(self: visp._visp.core.HomogeneousMatrix, tu: visp._visp.core.ThetaUVector) -> None
Insert the rotational component of the homogeneous matrix from a \(theta {\bf u}\) rotation vector.
insert(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.TranslationVector) -> None
Insert the translational component in a homogeneous matrix.
insert(self: visp._visp.core.HomogeneousMatrix, t: visp._visp.core.QuaternionVector) -> None
Insert the rotational component of the homogeneous matrix from a quaternion rotation vector.
insert(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D, r: int, c: int) -> None
Insert array A at the given position in the current array.
Warning
Throw vpException::dimensionError if the dimensions of the matrices do not allow the operation.
- Parameters:
- A
The array to insert.
- r
The index of the row to begin to insert data.
- c
The index of the column to begin to insert data.
insert(self: visp._visp.core.ArrayDouble2D, A: visp._visp.core.ArrayDouble2D, B: visp._visp.core.ArrayDouble2D, r: int, c: int) -> visp._visp.core.ArrayDouble2D
Insert array B in array A at the given position.
Warning
Throw exception if the sizes of the arrays do not allow the insertion.
- Parameters:
- A
Main array.
- B
Array to insert.
- r
Index of the row where to add the array.
- c
Index of the column where to add the array.
- Returns:
Array with B insert in A.
- static insertStatic(A: visp._visp.core.ArrayDouble2D, B: visp._visp.core.ArrayDouble2D, C: visp._visp.core.ArrayDouble2D, r: int, c: int) None ¶
Insert array B in array A at the given position.
Warning
Throw exception if the sizes of the arrays do not allow the insertion.
- Parameters:
- A: visp._visp.core.ArrayDouble2D¶
Main array.
- B: visp._visp.core.ArrayDouble2D¶
Array to insert.
- C: visp._visp.core.ArrayDouble2D¶
Result array.
- r: int¶
Index of the row where to insert array B.
- c: int¶
Index of the column where to insert array B.
- inverse(*args, **kwargs)¶
Overloaded function.
inverse(self: visp._visp.core.HomogeneousMatrix) -> visp._visp.core.HomogeneousMatrix
Invert the homogeneous matrix
- Returns:
\(\left[\begin{array}{cc} {\bf R} & {\bf t} \\{\bf 0}_{1\times 3} & 1 \end{array} \right]^{-1} = \left[\begin{array}{cc} {\bf R}^T & -{\bf R}^T {\bf t} \\{\bf 0}_{1\times 3} & 1 \end{array} \right]\)
inverse(self: visp._visp.core.HomogeneousMatrix, Mi: visp._visp.core.HomogeneousMatrix) -> None
Invert the homogeneous matrix.
- isAnHomogeneousMatrix(self, threshold: float = 1e-6) bool ¶
Test if the 3x3 rotational part of the homogeneous matrix is a valid rotation matrix and the last row is equal to [0, 0, 0, 1].
- Returns:
true if the matrix is a homogeneous matrix, false otherwise.
- load(*args, **kwargs)¶
Overloaded function.
load(self: visp._visp.core.HomogeneousMatrix, f: std::basic_ifstream<char, std::char_traits<char> >) -> None
Read an homogeneous matrix from an input file stream. The homogeneous matrix is considered as a 4 by 4 matrix.
The code below shows how to get an homogeneous matrix from a file.
vpHomogeneousMatrix M; std::ifstream f("homogeneous.dat"); M.load(f);
Note
See load(const std::string &) , save(std::ifstream &)
- Parameters:
- f
Input file stream.
load(self: visp._visp.core.HomogeneousMatrix, filename: str) -> None
Read an homogeneous matrix from an input file. The homogeneous matrix is considered as a 4 by 4 matrix.
The code below shows how to get an homogeneous matrix from a file.
vpHomogeneousMatrix M; M.load("homogeneous.dat");
Note
See load(std::ifstream &) , save(const std::string &)
- Parameters:
- filename
Input file name.
- static mean(vec_M: list[visp._visp.core.HomogeneousMatrix]) visp._visp.core.HomogeneousMatrix ¶
Compute the Euclidean mean of the homogeneous matrices. The Euclidean mean of the rotation matrices is computed following Moakher’s method (SIAM 2002).
Note
See vpTranslationVector::mean() , vpRotationMatrix::mean()
- Parameters:
- vec_M: list[visp._visp.core.HomogeneousMatrix]¶
Set of homogeneous matrices.
- Returns:
The Euclidean mean of the homogeneous matrices.
- numpy(self) numpy.ndarray[numpy.float64] ¶
Numpy view of the underlying array data. This numpy view cannot be modified. If you try to modify the array, an exception will be raised.
- orthogonalizeRotation(self) None ¶
Perform orthogonalization of the rotation part of the homogeneous transformation.
- resize(*args, **kwargs)¶
Overloaded function.
resize(self: visp._visp.core.HomogeneousMatrix, nrows: int, ncols: int, flagNullify: bool = true) -> None
This function is not applicable to an homogeneous matrix that is always a 4-by-4 matrix.
resize(self: visp._visp.core.ArrayDouble2D, nrows: int, ncols: int, flagNullify: bool = true, recopy_: bool = true) -> None
Set the size of the array and initialize all the values to zero.
- Parameters:
- nrows
number of rows.
- ncols
number of column.
- flagNullify
if true, then the array is re-initialized to 0 after resize. If false, the initial values from the common part of the array (common part between old and new version of the array) are kept. Default value is true.
- recopy_
if true, will perform an explicit recopy of the old data.
- save(*args, **kwargs)¶
Overloaded function.
save(self: visp._visp.core.HomogeneousMatrix, f: std::basic_ofstream<char, std::char_traits<char> >) -> None
Save an homogeneous matrix in an output file stream.
The code below shows how to save an homogeneous matrix in a file.
// Construct an homogeneous matrix vpTranslationVector t(1,2,3); vpRxyzVector r(M_PI, 0, -M_PI/4.); vpRotationMatrix R(r); vpHomogeneousMatrix M(t, R); // Save the content of the matrix in "homogeneous.dat" std::ofstream f("homogeneous.dat"); M.save(f);
Note
See save(const std::string &), load(std::ifstream &)
- Parameters:
- f
Output file stream. The homogeneous matrix is saved as a 4 by 4 matrix.
save(self: visp._visp.core.HomogeneousMatrix, filename: str) -> None
Save an homogeneous matrix in a file.
The code below shows how to save an homogeneous matrix in a file.
// Construct an homogeneous matrix vpTranslationVector t(1,2,3); vpRxyzVector r(M_PI, 0, -M_PI/4.); vpRotationMatrix R(r); vpHomogeneousMatrix M(t, R); // Save the content of the matrix in "homogeneous.dat" M.save("homogeneous.dat");
Note
See save(std::ofstream &), load(const std::string &)
- Parameters:
- filename
Output file name. The homogeneous matrix is saved as a 4 by 4 matrix.
- static saveYAML(filename: str, A: visp._visp.core.ArrayDouble2D, header: str =) bool ¶
Save an array in a YAML-formatted file.
Here is an example of outputs.
vpArray2D<double> M(3,4); vpArray2D::saveYAML("matrix.yml", M, "example: a YAML-formatted header"); vpArray2D::saveYAML("matrixIndent.yml", M, "example:\n - a YAML-formatted \ header\n - with inner indentation");
Content of matrix.yml:
example: a YAML-formatted header rows: 3 cols: 4 data: - [0, 0, 0, 0] - [0, 0, 0, 0] - [0, 0, 0, 0]
Content of matrixIndent.yml:
example: - a YAML-formatted header - with inner indentation rows: 3 cols: 4 data: - [0, 0, 0, 0] - [0, 0, 0, 0] - [0, 0, 0, 0]
Note
See loadYAML()
- Parameters:
- filename
absolute file name.
- A
array to be saved in the file.
- header
optional lines that will be saved at the beginning of the file. Should be YAML-formatted and will adapt to the indentation if any.
- Returns:
Returns true if success.
- t(self) visp._visp.core.ArrayDouble2D ¶
Compute the transpose of the array.
- Returns:
vpArray2D<Type> C = A^T
-
__hash__ =
None
¶